When you think about Microsoft, Bill Gates typically comes to mind. However, there's another hero to this story. While Microsoft co-founder and childhood friend of Gates, Paul Allen, tends to stay out of the headlines, his contributions to the famous tech company -- and humanity -- are impressive.

Having met Gates back in grade school in Seattle, the two bonded over their love of technology and computer programming. However three years older than Gates, Allen received a perfect score on his SAT and enrolled in Washington State University. Eventually, Allen dropped out of college and became a programmer for Honeywell in Boston while Gates attended Harvard University. Before long, Gates also left Harvard early and the two joined forces to create, what would eventually be known as, Microsoft.

After falling ill, Allen left Microsoft in 1983 and resigned from the board in 2000, yet continued to own a tremendous amount of shares in the company. Fast forward to today and Allen has a networth of $20.9 billion, is the founder and chairman of Vulcan Inc., the owner of two sports teams (the Seattle Seahawks and the Portland Trail Blazers) and the founder of multiple philanthropic foundations including the Paul G. Allen Family Foundation and the Allen Institute for Brain Science.

7. On motivation

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"In my own work, I've tried to anticipate what's coming over the horizon, to hasten its arrival and to apply it to people's lives in a meaningful way. The varied possibilities of the universe have dazzled me since I was a child, and they continue to drive my work, my investments and my philanthropy." -- Paul Allen